Korede is a meticulous nurse who keeps bleach in her car for a very specific reason: her younger sister Ayoola has a habit of killing the men she dates, always in self-defense, always with the same ornate ceremonial knife, and always calling Korede afterward to help clean it up. Oyinkan Braithwaite's debut novel runs under 240 pages, was longlisted for the 2019 Booker Prize, and became one of the most talked-about literary debuts of its year. This review works from what The New York Times and other outlets actually published, the real Goodreads numbers, and the specific, recurring places readers say the short novel doesn't quite go deep enough -- so you can decide honestly whether it's worth the afternoon it takes to read.
What My Sister, the Serial Killer Actually Is
The premise is stated outright in the opening pages, not withheld as a twist: Ayoola kills the men she dates, claims self-defense every time, and Korede -- older, plainer, permanently underappreciated -- is the one who shows up with cleaning supplies and a level head to make the evidence disappear. The novel isn't structured as a mystery about who's doing the killing; it's a character study of why Korede keeps protecting her sister anyway, especially once Ayoola starts dating a doctor Korede has quietly loved for years. Told in short, punchy chapters -- many barely a page or two -- set in Lagos, Nigeria, the book moves at the clip of a thriller while functioning more like a pitch-black family drama about the different currencies of loyalty, guilt, and beauty between sisters.
Braithwaite sets the entire novel in contemporary Lagos, and the setting isn't incidental -- hospital corridors, family expectations, and a culture that treats Ayoola's beauty as its own kind of armor all shape how far Korede is willing to go to protect her. The novel's short chapters and clipped prose give it a propulsive, almost cinematic pace that reviewers repeatedly singled out as distinct from typical literary fiction rhythms.
About Oyinkan Braithwaite and Why She Wrote This
Braithwaite was born in 1988 in Lagos, Nigeria, split her childhood between Lagos and London, studied law and creative writing at Kingston University in the UK, and moved back to Lagos in 2012, where she worked as an assistant editor at the publishing house Kachifo Limited before becoming a full-time writer. Before this novel, she'd built a smaller reputation as a spoken-word poet -- she was shortlisted as a top-ten performer in the 2014 Eko Poetry Slam -- and as a finalist for the 2016 Commonwealth Short Story Prize. My Sister, the Serial Killer is her debut novel, and by her own account it came out of a period of serious writer's block: she wrote it quickly, in roughly a month, as a way of breaking through a longer, stalled project rather than as a carefully architected literary debut. That speed shows up in the book's compression -- short chapters, minimal scene-setting, dialogue doing most of the work -- which reviewers have read as either a strength or a limitation depending on what they wanted from it.
What Critics Actually Said
Rather than inventing a verdict, here's what was actually published about it:
“A scorpion tailed little thriller.”— The New York Times
That's a short review line, but it carries real weight: the same paper later named the book to its list of Top Ten Thrillers of the 21st Century, and it was separately included on Time's list of the 100 Best Mystery and Thriller Books of All Time -- durable, repeated critical recognition rather than a single splashy opening notice. The novel was also longlisted for the 2019 Booker Prize, one of the most prominent literary awards in the English-speaking world, and shortlisted for the 2019 Women's Prize for Fiction, an unusual double-recognition for a book this short and this genre-blended. It went on to win the Los Angeles Times Book Prize for Mystery/Thriller, further confirming that critics across very different institutions landed on similar praise independently.
And the aggregate reader picture, for what it's worth:
Where Real Reviews Pushed Back
The most consistent, specific complaint across reader reviews is length and depth: because the book is so short and the chapters so clipped, several reviewers felt Korede and Ayoola never get the room to develop beyond their core dynamic -- the responsible sister and the charming, dangerous one -- and that the supporting cast, particularly the love-interest doctor, stays thin throughout. Some readers who came in expecting a conventional thriller with rising suspense and a twist ending were disappointed to find a book that states its premise upfront and stays fairly flat in tension across its length, since the pleasure here is closer to character study and dark comedy than mystery-plot mechanics. A smaller group found the ending abrupt, arguing the novel builds toward a question about what Korede will finally do and then doesn't fully resolve it. These are genuine, recurring critiques from engaged readers, not a dismissal of a widely admired book, and worth knowing before you pick it up expecting a slow-burn suspense novel.
On Sibling Loyalty as the Book's Real Subject
Braithwaite has said plainly that this is a book about family before it's a book about murder, and the text backs that up: the actual tension isn't whether Ayoola will kill again, it's how much of her own life Korede is willing to sacrifice to keep covering for her. Korede confides in a coma patient because she has no one else safe to tell; she watches her sister effortlessly attract the man she loves without being able to say a word. The killings function almost as a stress test for the sisters' bond rather than the point of the story itself -- an inversion of typical thriller structure that several critics singled out as the novel's most distinctive choice.
On Beauty, Attention, and Who Gets Believed
A second, quieter thread running through the novel is how differently Korede and Ayoola move through the world because of how each is perceived -- Ayoola beautiful and instantly trusted, Korede competent but overlooked. That imbalance is part of why Ayoola's self-defense claims go largely unquestioned by everyone except Korede: people are inclined to believe the version of events that comes from someone they find sympathetic to look at. Braithwaite doesn't editorialize heavily about this dynamic, but it's doing real work underneath the plot, and it's part of why reviewers read the novel as social commentary dressed in thriller clothing rather than a straightforward genre entry.
Key Takeaways
- The novel tells you who the killer is on page one -- it's a character study built around sibling loyalty, not a whodunit
- Real, durable critical recognition: a 2019 Booker Prize longlisting, a Women's Prize shortlisting, and a Los Angeles Times Book Prize win
- Braithwaite wrote it in roughly a month while breaking through writer's block on a different, longer project
- The most consistent reader criticism is that its short length leaves supporting characters and the ending feeling thin
- Set in contemporary Lagos, the novel uses beauty and perceived trustworthiness as a quiet, ongoing theme underneath the plot
Who This Book Is Actually For
Readers who want a fast, darkly funny read that can be finished in a single sitting -- particularly anyone drawn to morally complicated sibling relationships, unreliable trust, and pitch-black humor delivered in a lean, propulsive style. It's also a strong pick for readers newer to literary fiction who want something with real critical credibility that doesn't demand a long time commitment.
Who Should Read Something Else Instead
If you specifically want a slow-burn thriller with mounting suspense and a genuine twist, the documented criticism above is a fair warning -- this book states its premise from the first pages and stays there. Readers wanting deeper, more fully developed supporting characters may also find the brevity frustrating rather than efficient.
Pros and Cons
Pros:
- Genuine 2019 Booker Prize longlisting and Women's Prize for Fiction shortlisting for a debut novel
- Named to The New York Times' Top Ten Thrillers of the 21st Century and Time's 100 Best Mystery and Thriller Books of All Time
- Won the Los Angeles Times Book Prize for Mystery/Thriller
- Fast, propulsive pacing with short chapters that make it easy to read in one or two sittings
- Distinctive Lagos setting and dark humor rarely seen paired together in mainstream literary thrillers
Cons:
- Multiple reader reviews say the short length leaves supporting characters underdeveloped
- Not a conventional suspense thriller -- readers expecting mystery-plot mechanics may be disappointed by the flat tension
- A subset of readers found the ending abrupt relative to the questions the novel raises
Frequently Asked Questions
Is My Sister, the Serial Killer actually a thriller?
Not in the whodunit sense -- you know who's killing from page one. It's closer to a darkly comic family drama about sibling loyalty that happens to be built around a body count, which is why some readers who came expecting suspense mechanics were surprised by the tone.
What's the actual Goodreads rating?
3.63 out of 5 from more than 365,000 ratings as of this writing -- a huge rating count for a debut novel, reflecting how widely it was read as a book club pick. Check the live number yourself, since it keeps moving.
Did this book win any major awards?
It was longlisted for the 2019 Booker Prize and shortlisted for the 2019 Women's Prize for Fiction, and it won the Los Angeles Times Book Prize for Mystery/Thriller. It didn't win the Booker outright, but longlist recognition for a debut is real, documented literary attention.
What's the most common criticism of this book?
That it's short and moves fast enough that some readers wanted more depth from the two central characters -- a recurring note across reader reviews, alongside praise for its pacing and dark humor.
Sources & Further Reading
- Goodreads — My Sister, the Serial Killer (aggregate rating, reader reviews)
- The New York Times — review and Top Ten Thrillers of the 21st Century list
- The Booker Prizes — 2019 longlist author page for Oyinkan Braithwaite
- The Seattle Times — how Oyinkan Braithwaite came to write the novel
- PositiveLifes.com — free inspirational and life-changing PDF books
Final Verdict
My Sister, the Serial Killer backs up its buzz with real, durable recognition -- a Booker Prize longlisting, a Women's Prize shortlisting, and a spot on The New York Times' list of the century's best thrillers. The criticism about its brevity and thin supporting cast is legitimate and worth knowing going in, but for most readers that same compression is exactly what makes it work: a lean, propulsive read about how far loyalty can bend before it breaks. Set aside an afternoon; you'll likely finish it in one sitting either way.
Buy Day rating: 8.4/10